Just wanted to slightly alter/make slightly clearer the rankings that I gave in the first post regarding the dictionary+CD-ROM sets:

Winner, it's a toss up between the LDOCE4 and the MED. If you can live without the full-colour print of the Longman's paper dictionary, or the added bonus of the Language Activator on the CD-ROM, the MED is such a good dictionary (with a powerful CD-ROM also) that many might be as happy if not happier with it rather than the Longman set.

Runner-up: Cambridge Advanced Learner's (now in a Second Edition), although if the newer versions of the Oxford CD-ROM have more features than they used to offer, then I'd choose the OALDCE pack (because the OALDCE is certainly the better book of the two).

>>>Honourable mention: OALDCE7

COBUILD is now in a Fourth Edition, but you'd be better to try to pick up the Third (see earlier posts and antimoon.com for comments).

Regarding the books themselves/only, it is very hard to decide which is best out of the Longman, MED or Oxford (best to own 'em all, I say!), but I'll stand by my original rankings (these three in top position, followed by the once-innovative COBUILD, then the somewhat characterless Cambridge).

I usually refer to my Longman first (mainly for clear layout of frequency information i.e. the ordering of the words and phrases), but I also usually reach for the MED soon after (I often like the way it defines the function of a phrase); as for the OALDCE, it sometimes includes a phrase or idiom that isn't to be found in the other two dictionaries just mentioned, and its definitions can sometimes be clearer just by virtue of sometimes permitting a little more length and complexity in the phrasing.

American English: I've always been a fan of the Longman Advanced American Dictionary.

(Edit: Have just noticed that COBUILD now offer the above dictionary in bilingualized Korean and Japanese versions - see website link above - the Japanese version of which might compete with the Longman below):

Longman English-Japanese Dictionary (what appears to be a translation based on the LDOCE4. Note however that only headwords and example sentences are in English: signposts, definitions, notes etc are all in Japanese, so those wishing to compare definitions side by side in both languages might prefer the Oxford/Z-kai Wordpower dictionary mentioned previously, even though it is for the intermediate rather than advanced level and therefore less comprehensive overall)

Oh, I got the OALDCE7 book+CD-ROM pack, and the CD is as attractive as the book, and packed with enough features to now be able to challenge the LDOCE4(v2) for "best package on the market". The runner-up set is still the Cambridge, but the Macmillan set offers the superior book of the two.

Last edited by fluffyhamster on Fri Nov 07, 2008 10:05 pm; edited 2 times in total

It was interesting therefore to come across some research that compared learner performance using the CIDE versus the LDOCE3 (both published a while ago, in 1995, but still pretty representative of the modern MLD):
http://leo.meikai.ac.jp/~tono/userstudy/signpost.htm

The potted version of the findings is that the Longman seems to come out on top, which is what most people were probably suspecting would be the case.

BTW, Longman have released a very snazzy second edition of their Longman Advanced American Dictionary (it's similar to the full-colour LDOCE4, but perhaps looks even better to the eye).

At last! Macmillan have finally released a FREE online version of their MED (formerly, one had to prove one had bought a paper copy of the dictionary by answering questions about the contents of random pages). Hooray!
http://www.macmillandictionary.com/

[An adapted and enlarged version of a presentation to language teachers in Hong Kong on 17 Apr 04, at the launch of the 4th edition of the OALECD, a bilingualization by Lu Gu-sun, Zhuang Yi-chuan, and Shi Xiao-shu of the OALDCE, 4th edition.]